What is the barrel finish on SIG MCX upper conversion kits?

[ABNAK]

For the life of me I cannot find exactly what SIG barrels for these upper kits are done in: nitride or chrome lined? Or nothing? SIG's own website doesn't even say, nor do the numerous adds at vendor websites. Why are they so cagey about it?

Like this one:

UAMCX-16B-556-TAP

https://www.interstateguns.com/sig-s...b-556-tap.html

[Corse]

It depends. The commercial barrels are nitride. The mil/LE 556 barrels are chrome lined, but it appears that the 300 blk are nitrided according to Sig.

[ABNAK]

It depends. The commercial barrels are nitride. The mil/LE 556 barrels are chrome lined, but it appears that the 300 blk are nitrided according to Sig.

Can you post a source? Not being argumentative, just that I find it nowhere! I'd also like to know how one snags a mil/LE upper.

The SIG 516 commercial ones are nitrided, but the mil/LE ones are indeed chrome lined (I have one).

Would like something definitive on the MCX uppers before I drop coin on one. If it isn't at least nitrided then I won't touch it. Prefer chrome lined though.

[ABNAK]

Anyone have any recent information?

[Aries144]

Anyone have any recent information?

It looks like SIG uses nitrided barrels by default and only does chrome lining for government contracts that stipulate chrome lining.

[ABNAK]

It looks like SIG uses nitrided barrels by default and only does chrome lining for government contracts that stipulate chrome lining.

Yeah, that appears to be the case as most of the close-up pics of the uppers show that shiny black sheen on the barrel that is indicative of nitriding. I just wonder why you can't find it mentioned anywhere on their website.